Orthodontic tensioning assembly

ABSTRACT

A tensioning assembly for orthodontic instrumentalities comprising a coil compression spring housed in a tube and a tensioning member, e.g., a hook, adapted to compress the spring to apply traction to the teeth via an orthodontic instrumentality such as a face bow.

United States Patent 11 1 De Weoskin Nov. m, 1973 1 ORTHODONTIC TENSIONHNG ASSEMBLY FOREIGN PATENT-S OR APPLICATIONS lnvenwri Irvin De WeOskin, Louis, 915,317 11/1946 France 32 14 A [73] Assignee: Orthoband Company, Inc., St.

Primary Examiner Robert Peshock [22] Filed: July 20, 1971 Attorneyl(oenig, Senniger, Powers & Leavitt [21] Appl. No.: 164,250

Related US. Application Data 7 [57] ABSTRAQT [63] ggg g smr g of Sept A tensioning assembly for orthodontic instrumentalities comprising a coil compression spring housed in a [52] U S Cl 32/14 D tube and a tensioning member, e.g., a hook, adapted [51] 1". .Cl Amc 7/00 to compress the p g to pp y traction to the teeth [58] Fieid 4 A l 4 D via an orthodontic instrumentality such as a face bow.

[56] References Cited 5 21 Dmwmg F'gms UNITED STATES PATENTS 3,526,035 9/1970 Armstrong 32/14 D PAIENTEUMMO 1973 3.; 772,789

SHEET 3 BF 5 PAIENTEDnuvzo 1975 SHEET 5 OF ORTHODONTIC TENSIONING ASSEMBLY CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of my copending application Ser. No. 854,869, filed Sept. 3, 1969, and now abandoned entitled Orthodontic Tensioning Assembly.

BACKGROUND OF THE INVENTION This application is directed to orthodontic appliances or instrumentalities and more particularly to devices for applying tension to orthodontic devices which need to be placed under traction. These devices may be divided into two general classes, intra-oral devices and extra-oral devices.

Extra-oral devices are normally of the type in which the teeth are placed in traction via through tensioning means connected to a neck band or head band worn on the human neck or head. Traction is applied to the teeth via a maxillary arch band or a mandibular arch band for example. The tensioning means may include one hook or two, one on each side of the mouth. The hooks extend back on the sides of the face and are secured to the neck band or head band by the tensioning means. If the neck band extends around the back of the neck from ear to ear it is referred to as a cervical strap. If the head band extends around the back or the head from ear to ear, it is usually called an occipital strap. In the past the tensioning device used to connect the hook to the neck band or head band has commonly been an elastic band arrangement.

In intra-oral devices, ligatures, tension springs or rubber bands are usually attached to a group of teeth to apply traction thereto. The ends or the ligatures or springs are normally attached to metal bands attached to the outermost group of teeth being placed under traction. When rubber bands are used, they can be similarly attached to metal bands or they can be wound around the teeth themselves.

Use of an elastic band, i.e., a rubber band or other type of tension device has several disadvantages. It is difficult to precisely establish the desired amount of traction with such an assembly. Such an assembly can be pulled beyond the point of no return, in which case it no longer exerts traction, and it might even snap or break. In extra-oral devices, tension assemblies of this type have a tendency to catch on the hair of the patient. If a pad is provided on the device to provide greater comfort for the user, tension assemblies used in the past have had a tendency to catch and bind in the padding. Further, the amount of movement in the tension device required to develop a given amount of traction on the orthodontic appliance has frequently been unsatisfactory. The more traction required in such an assembly, the more the device must be stretched making it longer, and hence the head or neck band has to be taken up to compensate for this greater length. There is a tendency for the tension assembly in intra-oral devices to pick up contaminating food particles or irritate the oral tissues.

SUMMARY OF THE INVENTION Among the several objects of the instant invention may be noted the provision of a tensioning assembly for orthodontic instrumentalities in which the traction is developed by compressing a member rather than by applying tension to it. It is an advantage of such a tensioning assembly that it cannot be pulled beyond its point of no return in developing traction. It is so constructed that it cannot catch on the hair of the patient, will not bind in padding and takes less movement than conventional devices to develop a given amount of traction. It is a further object of the instant invention to provide such a tensioning assembly which is completely encased so that when used intra-orally, it cannot pick up contaminating food particles or irritate the oral tissues. It is a further object of the instant invention to provide a tensioning assembly which will give a more precise and longer lasting traction than the orthodontic tensioning assemblies heretofore known.

The assembly includes a coil compression spring housed in a tube and a tensioning member, e. g., a hook, adapted to compress the spring to apply tension to an orthodontic instrumentality in the mouth of a patient.

Other objects and features will be in part apparent and in part pointed out hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a front perspective illustrating an orthodontic device with a compression spring as it is worn on the human neck;

FIG. 2 is a back perspective of the device as worn in FIG. 1;

FIG. 3 is an enlarged side elevation of part of the orthodontic appliance;

FIG. 4 is a view of a variation of the appliance of FIG.

FIG. 5 is a view of another variation of the appliance of FIG. 3;

FIG. 6 is a view of an embodiment of the instant invention useful in applying traction to an intra-oral orthodontic device;

FIG. '7 is a sectional view of the device of FIG. 6;

FIG. is a sectional view of a variation of the device of FIG. 6;

FIG. 9 is a view of another embodiment of the instant invention useful in developing extra-oral traction;

FIG. 10 is a sectional view of the device of FIG. 9;

FIG. I] is a view of a variation of the device of FIG.

FIG. 12 is a sectional view of the device of FIG. II;

FIG. 13 is a view of another variation of the device of FIG. 9;

FIG. 14 is a sectional view of the device of FIG. 113;

FIG. 15 is a view of another variation of the device for intra-oral use;

FIG. 16 is a variation of the device of FIG. 15;

FIG. 17 is a view of an intra-oral embodiment of the instant invention applied to teeth;

FIG. I8 is a view of another embodiment of the instant invention for extra-oral use;

FIG. 19 is a view in elevation of another embodiment;

FIG. 20 is a plan of FIG. 19; and

FIG. Zll is an enlarged longitudinal section on line 2ll2I of FIG. 26.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS -Referring now particularly to FIGS. I-S, a strap or neck band 1 may be seen extending around the back of a human neck, from one side of the head to the other. In general, neck band 1 is of such length as to be capable of extending around the back of the neck (the cervix) from ear to ear. According, it constitutes, and is frequently referred to as, a cervical strap. A hook fastener 3 is shown attached to the end of neck band 1. Engaged in hook fastener 3 and extending therefrom is a clip 5 constituting a fastening means which is clipped to a guard tube 7. Tube 7 is positioned around and extends the length of resilient compression spring 9. The end of tube 7 opposite to that fastened to clip 5 is attached, as by staple 10, to compression spring 9. Tube 7 slidably supports compression spring 9. It will be observed that tube 7 (via staple 10) engages one end (the forward end) of the resilient compression spring 9 and extends past its other end so as to form a projection thereform.

Extending through the hollow of spring 9 is a doubled-over rod 11. The ends 13 of rod 11 are attached to the end of spring 9 adjacent neck band I (the rearward end of the spring). As shown, this can be done simply by bending the end 13 of rod 11 outwardly around spring 9. The rod 11 extends through the hollow of spring 9 forming a projection means and is fastened at its bight 15 to a fastening means constituted by closed hook 19 at the end of a connector 17. Each connector 17 (two being shown in FIG. 1) is formed in the shape of a hook and is adapted to be attached to, for example, an arch band for the maxillary arch (the upper teeth), not shown, within the mouth of the patient shown in FIG. 1. From the figures it can be readily seen that when the ends of tube 7 and the bight 15 of rod 11 are pulled in opposite directions the resilient compression spring 9 will be compressed applying tension to the orthodontic instrumentality, biasing hook 17 toward neck band 1 and placing the orthodontic appliance, the arch band, under traction.

FIG. 4 shows a variation of the FIG. 3 device. In this figure the fastening means for connecting hook 17 and neck band 1 to compression spring 9 have been reversed. That is, hook 17 is now connected to tube 7 and neck band 1 is now connected through hook fastener 3 to doubled-over rod 11 at its bight 15.

Fig. 5 shows still another variation of the FIG. 3 device. Here both the 17 and the neck band 1 are fastened to the bights 15 ofa pair of doubled-over rods 11.

Referring now to FIGS. 6 and 7, an embodiment of the instant invention suitable for applying traction to intra-oral orthodontic devices may be seen. Here one end 21 of tube 7, formed ofa suitable metal such as aluminum or steel, is affixed to a fastening means shown as rod 23. The other end 25 slidably supports the other projection means shown as rod 27. Rod 27 is adapted to be attached at one end 29 to a suitable fastening means. Second end 31 of rod 27 is enlarged and is positioned in force transferring relationship to an end 33 of spring 9.

FIG. 8 shows a variation of the device of FIGS. 6 and 7. As shown, tube 7 has first and second end closures 21, 25 each having a restricted opening therein. A first resilient compression spring 9 has one end 33 engageable with first end closure 21 and is adapted to react against it. A first tension member shown as rod 35 has one end 37 engageable with the other end 39 of first compression spring 9 within tube 7. Rod 35 extends lengthwise of first compression spring 9 through the restricted opening in first end closure 21. A second resilient compression member or spring 41 is positioned in the tube so as to have one end 43 engageable with second end closure 25 and is adapted to react against it. A second tension member in the form of rod 45 has one end 47 engageable with the other end 49 of second compression spring 41 within tube 7 and extends lengthwise of spring 41 through the restricted opening in second end closure 25. The ends 48 and 51 constitute means for fastening rods 35 and 45 to an orthodontic instrumentality on a patient so that the tension members or rods 35 and 45 are pulled in opposite directions whereby the resilient springs 9 and 41 are compressed applying tension to the orthodontic instrumentality.

Referring now to FIGS. 9 and 10, another embodiment of the instant invention may be seen. As shown in these figures, projection means or rod 27 is formed integrally with the hence is permanently fastened to face bow 17 which constitutes the means for fastening the projection means to the orthodontic appliance (the arch band). End 21 of tube 7 is closed and has an eye opening 53 therein for engagement with a fastening means, e.g., the hook fastener of a neck band. In this embodiment the tube 7 is made ofa heat-sealable plastic such as fluoropolyethylene, and is sealed to itself at one end 21 with an eye opening 53 formed therein and sealed to itself at end 25 around the slidable projection formed by rod 27 to form a sliding seal with respect thereto. A lubricant such as grease 55 may be provided within tube 7 for lubricating spring 9.

The embodiment of FIGS. 11 and 12 is similar to that of FIGS. 9 and 10 except here end 21 of tube 7 is sealed and anchored to fastening means 57.

FIGS. 13 and 14 illustrate an embodiment of the invention which is similar to that shown in FIG. 8 and is suitable for use with extra-oral appliances. Whereas tube 7 is shown as formed ofa metallic material in FIG. 8, it is formed of heat-scalable plastic in the embodiment shown in FIGS. 13 and 14. Fastening means 57 is attached to and integral with tension rod 35. Hook 17 is permanently fastened to rod 45 and hence the fastening means is an integral part of rod 45. The ends 21, 25 of tube 7 are heat sealed around rods 35 and 45 so that restricted openings for passage of rods 35 and 45 result which constitute sliding seals with respect thereto.

FIG. 15 shows a device similar to that of FIG. 9 suitable for use in connection with intra-oral orthodontic appliances. In this embodiment the fastening means is formed by the end of rod 27 being bent to form a loop fastener 59. Heat-scalable plastic is used to form tube 7 in this embodiment as compared with a metal such as aluminum or stainless steel to form tube 7 in the intraoral embodiment shown in FIGS. 6 and 7.

FIG. 16 is of a device similar to that of FIG. 15 with the exception that the projection means is a ligature 61 having a first end 63 constituting a fastening means and extending through spring 9 to the end 33 thereof and having an enlarged second end 31 (for example, formed by a knot) in force transferring relationship to end 33 of spring 9. A second ligature 65 is shown as constituting a fastening means attached to eye opening 53 in end 21 of tube 7.

FIG. 17 shows a device such as that shown in FIGS. 6 and 7 in use. Ends 29 and 67 of rods 27 and 23 constitute fastening means for attaching the rods to metal bands 69 in any suitable manner, for example, by clamping, soldering or welding. In FIG. 17, ends 29 and 67 are shown attached by clamps '75 to bands 69. Metal bands 69 are affixed to the teeth 7ll in a manner well known to practitioners of orthodontia. The arrangement of the device is such that the projection means constituted by rods 27 and 23 are pulled in opposite directions, compressing spring 9 (HO. 7) which applies tension to the orthodontic instrumentality, i.e., bands 69, and hence places the teeth 71 under'traction. It will be observed that since spring 9 is completely enclosed in tube 7, it cannot pick up contaminating food particles or irritate oral tissues.

FllG. in illustrates another embodiment of the instant invention. As shown, rod 27' has a fastening means 5'7 affixed to one end thereof. Tube '7 is formed of a transparent material and carries indicia or scribe marks 73 thereon. Means within the tube such as end dll of rod 2'7 traverse the indicia or scribe marks '73 and indicate the force generated by spring 9 when the projections are drawn apart. This will facilitate establishing the desired amount of traction every time the device is placed into use in connection with the application ofan orthodontic appliance to a patient.

FllGS. l92it illustrate still another embodiment of the invention similar to the embodiment of FIG. 9 wherein the elongate tubular member or tube is again designated '7, the spring 9, and the hook 117. The tube '7 in this instance is also made of a heat-scalable plastic such as fluoropoly-ethylene. The spring 9 again is an elongate coil compression spring and is housed in the tube '7 extending lengthwise thereof. The tube 7 has one end thereof which may be referred to asits forward end, formed into an inwardly extending integral flange 8i constituting a closure for the tube at this end. This flange or closure till bounds a central opening $3 at the end of the tube, and provides an abutment for the respective end of the spring 9. The tube 7 is closed at its other end which may be referred to as its rearward. end, as indicated at Zla by being pinched flat, and by having its opposed walls in the pinched-flat end portion heatsealed together. An opening or eye 53a is formed in the pinched-flat closure Zia and the latter is reinforced around the opening 53a by means of a metal grommet 955 secured in the opening.

The length of the spring 9 when uncompressed is somewhat than the distance from the inner region of the pincheddlat closure T hos, with the forward end oi the spring engaging closure iii, its rearward end is spaced from closure Jilin. The hook i? (which constitutes the tensioning member of the appliance) has a straight shanlt ll'icz which extends into the tube 7 through the opening 933, having a sliding lit in the latter whereby the opening 99 is at least substantialiy closed by the shank. The shank il'l n extends through the spring 9 and has means indicated at it? at its inner end having a sliding lit in the tube Ti and engaging the end of the spring 9 remote from closure bl. This means as shown in hit fill, is constituted by a ball (which may be bead oi a head chain, for example) seated in the end oi the spring and having diamctricnl passage therethrough in which the shank ila has a rotatable tit. The shank has a head M1 at its inner end engaging the ball h"? and extends generally axially through the spring and through opening did and out of the end oi the tube. The head 9i may be expeditiously provided sirnply by flattening the end oi the shank.

W69. 99 and ill show two of the tubes l secured to l'lOOliS and 9.9 at the ends or" a cervical band in similar to that indicated at l in FllGS. ii and 2, the llOOitS and 95 being hooked into the grommets 85 at the pinched-flat closures Ella of the tubes. As shown, the band is of adjustable length, having a loop 97 receiving the hook 95 and a clasp 99 adapted to be released for adjustment of the size of the loop, and then retightened. The traction applied by the two tube devices of FIGS. ll9 and 2'0 to the teeth may be decreased or increased, with the capability of infinite adjustment within the overall range of adjustment, by lengthening or shortening the band in.

With particular regard to the device shown in FiGS. ll9-2i, it will be observed that the tube 7 is essentially wholly closed against entry of contaminants. The shank ll'7a of the hook ll7 is maintained in accurate alignment, i.e., maintained coaxial with the tube within the spring 9 via its sliding fit in opening 83 and via the ball 87 which centers the inner end of the shank in the tube and has a sliding fit in the tube. There is low friction between the ball and the tube. On any rotation of the shank ll7a on its axis, it simply rotates within the passage 299 in the ball, without twisting or imposing any torque on the spring, thus eliminating any possibility of variation in the traction force applied by the spring on account of rotation of the shank. With spring 9 being a compression spring, light wire may be used therefor; it cannot be distorted where a tension Spring, by contrast, may bestretched beyond its elastic limit unless its stretch is limited. With the grommet at one end of the tube, the device is readily applicable not only to the cervical band type of appliance for downward pull, but also to high-pull and low-pull headgear.

it can readily be seen that the compression spring cannot be pulled beyond its point of no return to de velop traction since it is not being placed in tension but only in compression. The arrangement is such that the spring is not likely to catch on the hair of the patient or to bind in other parts of the orthodontic appliance. A compression assembly according to the instant invention requires less movement to develop a given amount of tension or traction than conventional te-"- sioning devices incorpmat pression members may metallic or nornrnet .l

up containin lint" sues if used in conn the skin of the fac oral device.

The instant invention can be incorporated in devices of various sizes. The invention can he made microminiature to be titted between oa oraily a replacement ior intra-oral ligatures or spings or wires. it may be sheathed eithc ic metal tubes with either straight or arctroral tubes can be var using adjustment hue sion wili inc" rnent strap and less adjustment strap or hold vice.

in view of the above, it will seen that several objects or" the invention ochie'wed and other advan tageotis ts at incd.

As various ch es can he made the above constructions without arting from oi vention, it is intended traction deabove description or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. A tensioning assembly for orthodontic instrumentalities comprising an elongate tube having a first end closure at one end constituting its forward end and a second end closure at its other end constituting its rearward end, said first end closure having a generally central opening therein, an elongate coil compression spring housed in the tube extending lengthwise thereof, said Spring having one end constituting its forward end engaging the first end closure and extending back in the tube with its other end constituting its rearward end spaced from the second end closure, a tensioning member extending generally axially through the spring within the tube and extending out of the forward end of the tube through said opening and having a sliding fit in said opening, means on the tensioning member within the tube between the rearward end of the spring and said second end closure having a sliding fit in the tube and engaging the rearward end of the spring, and means at the rearward end of the tube for anchoring it in place for applying traction to the teeth via extension of said tensioning member from the forward end of the tube and resultant compression of the spring by the said means which engages the rearward end of the spring.

2. A tensioning assembly as set forth in claim 1 wherein the tube is formed of heat-sealable plastic material and the second end closure is formed by the rearward end of the tube having been pinched flat and heatsealed.

3. A tensioning assembly as set forth in claim 2 wherein the pinched-flat end of the tube has an eye and a grommet in the eye constituting said anchoring means.

4. A tensioning assembly as set forth in claim 3 wherein said tensioning member comprises a hook having a straight shank extending through said opening and said spring, the shank extending rotatably through said spring-engaging means so as to be rotatable on its axis without twisting the spring, and having a head at its rearward end engaging said spring-engaging means.

5. A tensioning assembly as set forth in claim 4 wherein said spring-engaging means comprises a ball seated in the rearward end of the spring. 

1. A tensioning assembly for orthodontic instrumentalities comprising an elongate tube having a first end closure at one end constituting its forward end and a second end closure at its other end constituting its rearward end, said first end closure having a generally central opening therein, an elongate coil compression spring housed in the tube extending lengthwise thereof, said spring having one end constituting its forward end engaging the first end closure and extending back in the tube with its other end constituting its rearward end spaced from the second end closure, a tensioning member extending generally axially through the spring within the tube and extending out of the forward end of the tube through said opening and having a sliding fit in said opening, means on the tensioning member within the tube between the rearward end of the spring and said second end closure having a sliding fit in the tube and engaging the rearward end of the spring, and means at the rearward end of the tube for anchoring it in place for applying traction to the teeth via extension of said tensioning member from the forward end of the tube and resultant compression of the spring by the said means which engages the rearward end of the spring.
 2. A tensioning assembly as set forth in claim 1 wherein the tube is formed of heat-sealable plastic material and the second end closure is formed by the rearward end of the tube having been pinched flat and heat-sealed.
 3. A tensioning assembly as set forth in claim 2 wherein the pinched-flat end of the tube has an eye and a grommet in the eye constituting said anchoring means.
 4. A tensioning assembly as set forth in claim 3 wherein said tensioning member comprises a hook having a straight shank extending through said opening and said spring, the shank extending rotatably through said spring-engaging means so as to be rotatable on its axis without twisting the spring, and having a head at its rearward end engaging said spring-engaging means.
 5. A tensioning assembly as set forth in claim 4 wherein said spring-engaging means comprises a ball seated in the rearward end of the spring. 